The Team Fortress 2
Website has another scolding from the TF Announcer, who is dismayed to learn
players are unlocking Team Fortress 2 achievements by cheating, forcing a
few week-long suspensions:

This time it seems a number of you used an
external application to unlock all of your achievements in order to get items
unfairly. Coming as a surprise to no one with the ability to retain memories of
the recent past, I have taken these items from the perpetrators for one week.

Can I trust that this episode has finally taught you a lesson? I should live so
long. Having watched how the sorry lot of you comport yourselves on the
battlefield and in the forums, I would consider it a small miracle to trust one
of you enough to lick stamps without asphyxiating.

I only bought TF2 yesterday so I don't really give a damn about achievements yet as I still can't use the default weapons for shit, but I think the rampant attempts to circumvent the achievement system is enough to suggest something isn't right.

Perhaps you will always just get that sort of thing, but to my mind, achievements should be things that encourage players to play the game as they normally would, supporting their teammates, but with more skill. It ought to be along the lines of 'steal the enemies intel X many times in Y many minutes'--something you would otherwise be doing anyways, but with the encouragement to try yet harder.

If the achievements are so ridiculously laid out that you have to abandon the spirit of the game and your teammates solely to earn some far flung achievement for yourself, it's probably just as well that people are using achievement servers or cheat apps instead of mussing up proper servers with their antics.

As has been mentioned before, make the achievements more along the lines of military decorations--something that you can flaunt that demonstrates your skill, not an entirely new gameplay element. The weapons they just ought to give you.

All the same, the third party app is definitely cheating, regardless of whether or not it gives players an advantage. The achievement servers are cheap for sure, but IMO still within the bounds of fair play, though boring, grinding, OCD-rife, fair play of course.